The present invention relates to interactive information displays and, more particularly, to an electroscopic matrix-addressed display having a data input capability provided by a magnetic stylus.
Electroscopic information output displays are described and claimed in co-pending U.S. patent application Ser. No. 303,275, filed Sept. 17, 1981, now U.S. Pat. No. 4,420,896, issued Dec. 20, 1983, and incorporated herein by reference in its entirety. These electroscopic displays are bi-stable displays, typically of the matrix type, in which displayed information is stable as long as a holding voltage is applied. If the voltage at a display cell is briefly reduced below a first value, the cell will turn "off" and become highly light-absorptive, whereas if the voltage at a particular cell is briefly increased above a second value, the cell will turn "on" and become highly light-reflective. Thus, a potentially low-cost, multiplexible output information display is provided.
For interactive information devices, an input data capability is required as well as the data output display capability. If a separate data input device is utilized, the cost is typically significantly increased; if two physically-separated devices are utilized, parallax and registration problems are often encountered. It is therefore highly desirable to provide an electroscopic display device having a data input capability, whereby the input and output functions can be combined in a single relatively-flat panel device.